Could ancient humans really have built the pyramids without extraterrestrial help? Or do such questions reveal more about modern anxieties than the past itself?

Here's the latest from the New Mexico sheriff's office searching for retired U.S. Air General William Neil McCasland.

Renewed attention is falling on the base after the disappearance of retired Air Force Maj. Gen. William Neil McCasland.

McCasland, 68, went missing from his Albuquerque home on Feb. 27 — which is the same day that a conspicuously credentialled X ...

Maj. Gen. William Neil McCasland, who retired from Wright-Patterson Air Force Base near Dayton, Ohio, is missing in New ...

Add Yahoo as a preferred source to see more of our stories on Google. Engineers create 'alien-like' AI robot that can evolve and repair itself. Engineers in the United States have created AI-powered ...

A retired general from the Air Force has mysteriously disappeared in the wake of Trump announcing the release of government’s UFO-related files.